JPS6080500A - Control of recirculation type clothing dryer - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention (a) Industrial Application Field The present invention cools the exhaust air from the drying chamber with a dehumidifier to remove moisture, then reheats it with a heater and supplies it to the drying chamber. The present invention relates to a circulating clothes dryer having a circulating air path.

Conventional technology In most conventional dryers, the operating time was determined by the user using a timer based on the type, amount, moisture content, etc. of the clothes. If the drying time is too long, or if the drying is insufficient, you should not try drying again.Therefore, the exhaust temperature from the drying room was adjusted to a degree of dryness of 80%.
The temperature difference between the outside air temperature and the exhaust gas temperature is detected by taking advantage of the fact that the temperature rises rapidly when the temperature reaches about Japanese Unexamined Patent Publication No. 19296/1983 proposes a device in which drying is terminated when the difference between the temperature and the exhaust temperature becomes larger than a predetermined constant value.

However, this device detects the outside air temperature as a temperature to compare with the exhaust temperature, and this outside air temperature becomes unstable when the dryer is used indoors (in this case, the outside air temperature becomes the indoor temperature). Also, when the air volume changes due to filter clogging or the 1L source voltage changes, the exhaust temperature changes and the outside air temperature does not respond to this change, making it difficult to always perform accurate control, resulting in drying. There was a risk that the drying process would be completed without drying too much.

Furthermore, when the amount of clothes to be dried is small, the difference between the inside air temperature and the outside air temperature rises once, becomes almost constant, and then goes down again, and sharply rises again when the drying rate reaches about 80%. Because it shows the change (tore is, if there are few clothes,
In the early stage of drying, the hot air that enters the drying chamber is exhausted without touching the clothes, increasing the uF air humidity and temperature.When the clothes have dried to a certain extent, they loosen and spread out, and the clothes are exposed to hot air before being exhausted. This is because the exhaust temperature decreases once. ) There was a risk that the difference between the exhaust gas temperature and the outside air temperature, which was once stored as a reference value, would be inaccurate, resulting in excessive dryness.

(c) Purpose of the Invention An object of the present invention is to provide a circulating clothes dryer that can detect a certain level of dryness and end drying without being influenced by external factors such as outside air temperature, and that is To provide a control method capable of obtaining a desired drying rate even when drying clothes on the spot.

(2) Structure of the Invention The present invention provides that in a circulating clothes dryer, one part of the circulating air passage, σ
Focusing on the fact that the temperature after passing through the drying chamber and the temperature after passing through the dehumidifier in the cooling air path shows stable changes during drying and changes depending on the exhaust temperature from the drying room, a first heat-sensitive element for measuring the temperature of the air before passing through the dehumidifier, that is, the temperature of the exhaust air from the drying room; The device is equipped with a heat-sensitive element (vj2) that measures the temperature of the air after it has passed through the dehumidifier in the cooling air passage, and the temperature measured by the heat-sensitive element is measured after a predetermined period of time has elapsed from the start of operation. When the difference reaches a substantially constant value, that temperature difference is stored as a reference value, and when the difference in the measured temperature becomes lower than this stored reference value, this lowered temperature difference is replaced as a new reference value, and this temperature difference is replaced as a new reference value. The drying operation is terminated when the measured temperature difference reaches a predetermined value or more than the reference value determined in this manner, or after a certain period of time has elapsed thereafter.

(E) Embodiment An embodiment of the present invention will be explained based on the drawings. (1) is an outer box, the rear opening of which is closed off by a back plate (2), and the front side of the box is provided with a clothes slot (4) which can be opened and closed by a door (3). (6) is a drum that serves as a drying chamber for storing clothes, and a front plate (9) is firmly attached to the 111 end of its peripheral wall (7), and the edge of this front plate (9) is firmly attached to the front of the outer box. It is fitted to the outer peripheral flange (12) of the drum support plate (11) via a sliding member such as a soldering member (13).

A shaft (14) is protruded from the center of the rear wall (8) of the drum (6), and this shaft (14) is inserted into a cylinder (16) formed at the center of the support plate (15). (17), and the tip of the shaft body (14> is
) to prevent the shaft (14) from coming out of the cylinder (16).The support plate (15) has both ends as shown in Fig. Flanges (20) (21) formed at the rear ends of the upper and lower surfaces of the outer box (1)
) is completely stuck.

The rear wall (8) of the drum (6) has a plurality of air discharge holes (
22), and a rear tact (23) that communicates with the inside of the drum (6) through this discharge hole (22) is connected to the support 1.
It is fixed at ff(15). The discharge hole (22) is provided with a removable filter cover (24) having a filter net (24).
25). 26> is the rear duct (23)
This is a hole member that prevents air leakage between the rear wall (8) of the drum (6) and the rear wall (8) of the drum (6).

The outlet (33> of the rear duct (23) is connected to the suction chamber (36) of the circulation fan casing (35) via a connecting pipe (34). (3) As shown in the figure, a circulation fan (37) consisting of a centrifugal fan is provided.
37> is a small pulley fixed to its shaft (38) - <39
) is connected to the shaft (42〉) of the motor (41) by the belt (40).
It can be rotated completely by being connected to a dog pulley (43) fixed to. A small pulley (44) is also fixed to the shaft (42) of the motor (41>), and by winding a belt (45) between this small pulley (44) and the outer circumference of the drum (6), the drum ( 6) is also rotated at low speed. Figure 2) (46) is the eye [° Labouly] that adjusts the tension of Hell 1 (45).

A discharge tact (47) of the circulation fan casing (35) is communicated with one end side of a large number of vibes (49) of the dehumidifier (48). The dehumidifier (48) has this many vibes (49)
and a large number of cooling fins (50) perpendicular to the vibrator. In Figure (3), (51) is a cooling fan, which is installed inside a cooling fan casing (52), and a suction duct (53) of this casing (52) is connected to the outside air which opens on the top surface of the outer box (1). It is connected to the intake port (54), and the discharge tubes 1 to (55) are connected to the upper end surface of the cooling fif 50). The cooling fan (51) is fixed to the shaft (38) of the circulation fan (37). Then, as the cooling fan (51) rotates, outside air is sucked in from the outside air intake port (54) through the filter (61) as shown by the dotted line arrow in Figure (3) and sent to the mechanical cooling fins (50). A cooling air path is formed by cooling the moist, warm air passing through the inside of the box, condensing the moisture contained therein, and exiting through the numerous exhaust holes (56) provided on the bottom of the outer box. On the other end side of the large number of vibrators (49), there is a front duct h
One end of the front duct (57) is connected, and the condensed water is connected to a drainage hole (11>) connected to the lower surface of this front duct (57).
) and the drum (6).
) is provided. Furthermore, a heater black 0> is installed inside the duct (57).

Then, when the heater (60) is energized and the motor (41) is rotated, the circulation fan (37), the cooling fan (51), and the drum (6) rotate, and as shown in FIGS.
4) Drum (6) from the intake hole (59) as shown by the solid arrow in the figure.
When the heated air is completely supplied to the inner heater (60)-C' and the moisture is evaporated from the clothes in the drum, this hot and humid air flows into the Mii filter cover (25) and the discharge hole (2
2) into the rear duct (23), and is discharged from the rear tact (23) through the connecting pipe 34) to the dehumidifier.
48) to a number of vibes (49), as previously described here.

It cools down and the moisture contained in it is condensed, and then it is sent through the front duct (57) to the heater (60) and heated again, and then the air is pumped through the intake hole (59) to the drum 1-(6).
＼Repeat the cycle of being supplied. Solid arrows represent circulation air paths.

Therefore, inside the discharge tuff l-<47) of the circulation fan casing (35), there is Bi which passes through the dehumidifier in the circulation air path.
A first heat sensitive element (61) is provided to measure the temperature of the positive air, ie the drum exit temperature. Here, a thermistor is used as the heat-sensitive element (61).

In addition, a dehumidifier is installed below the dehumidifier (48) in the cooling air path described in iii.
A second heat sensitive element (62), also a thermistor, is provided to measure the air temperature after passing through the dehumidifier, ie the dehumidifier outlet temperature.

Next, the control circuit will be explained based on Figure 5) (63
) is the power-on switch, (64) is the first door switch, (41) is the motor, and (60) is the heater. (65> is a DC converter circuit, which converts the DC voltage into a rectangular wave in a waveform shaping circuit (66), and applies this pulse to a microcomputer (67) for time counting. (68) is the clock J1 circuit, which generates pulses used to advance the program in the microcomputer (67). (6
9) is an initialization circuit, and when the power supply switch (63) is pressed, this initialization circuit operates and the program in the microcomputer (67) is set to the initial state. - to be done. (61) is the thermistor which is the first heat-sensitive element, and (62) is the thermistor which is the second heat-sensitive element of Nii.

They are connected in series with resistors (70) and (71), respectively, and their respective divided voltage values are input to voltage comparators (72) and (73). Also, the other input terminal of each voltage comparator (72) (73) is input with the output signal of the ladder circuit (74) which receives the output from the microcomputer (67) and generates a staircase wave. Ru. This ladder circuit is connected to the output terminals (A), (B), ... (G) of the microcomputer (67), and as the signals are sequentially output from each output terminal, the output voltage of the ladder circuit (74) increases. When the voltage comparators (72) and <73> conduct and there is an input to the 1j computer (67) from 71', it changes to the output terminal (
The microcomputer itself determines which terminal (A) (B) or (G) the signal is output from, and determines the drum exit temperature of the circulation air path and the dehumidification mold temperature of the cooling air path. (77) is the second door switch to determine whether the clothes loading door is closed or not.
(78) is a 50/60Hz changeover switch, and (75) is a start switch for starting the drying operation. (7
9) is the first relay winding, and the start switch <75
), an output signal from the microcomputer (67) causes a current to flow through the transistor to the first relay winding (79), and the first relay contact (
79') is closed to energize the motor (41). (80λ is the second relay winding, (81) is a light emitting diode for drying operation display, and when the drying process has proceeded to j, a signal output from the microcomputer (67) is sent to the Ai + light emitting diode 1) via a transistor. Turn on the electricity and turn it on to indicate that it is in the drying process.
At the same time, by energizing the second relay winding (80), the second relay winding (80) is energized.
Close the relay contact <80') and close the first door switch (64').
c (84) is a light emitting diode for indicating the cold air operation that lights up during the cold air operation. (
86) is a power plug.

The operation of the above configuration will be explained below. When the power-on switch (63) is pressed, a DC voltage is applied to the microcomputer (67) through the DC conversion circuit (65), and the input/output circuit (69) is activated to turn on the circuit in the microcomputer. Return the grams to their initial state. The program is sequentially advanced by signals from the clock oscillation circuit (68). First, the thermistor (61) is the first heat-sensitive element, and the thermistor (62) is the second heat-sensitive element.
), ladder circuit (74) voltage comparator (72) (73)
The temperature at the drum outlet 1 and the dehumidifier temperature are determined by θ at 1 second intervals, and the values are input to the microphone 17 computer.
) is stored in RAM (readable memory). Press the start switch (75), and if the clothes loading door (3) is closed, open the first and second door switches (64).
The microphone computer (67) detects that the 21st winding (77) is closed and the 21st winding (77) is closed, and the output current is sent to the 1st L-1 winding (79). The first relay contact (79') is closed, and the motor (41) is energized to heat the drum (6) and both fans (37) (5).
At the same time, the second relay winding (80
) + main output' current is output and the second relay contact (80) Σ
Then, the heater (60) is energized to start drying operation. The combinator (67) converts the current wave into a waveform shaping circuit <S6>-C and converts it into a rectangular wave by counting the number of pulses and counts the operating time. This old enemy is R
A specific address in M is used as a time counter for downward blowing, -
The time is updated every minute.

By the way, the difference between the drum outlet temperature and the dehumidifier outlet temperature measured by the first and second heat sensitive elements (61>(62>r) changes approximately as shown in Fig. (6) during the drying operation.

That is, during the period after the start of the drying operation, the temperature difference between the two temperatures increases, or once it reaches a certain temperature difference (A), it reaches a steady state and stops changing. In this steady state, the temperature difference begins to increase, but the drying rate at this time is approximately 80%.

Therefore, in Figure (6), whether the above two temperatures are different (A and B)
) degrees (where B is a predetermined positive number), if the drying operation is stopped, the operation can be completed with a drying rate of about 90%.

Note that the time required for the above two temperature differences to become approximately constant (T
1) is determined by experimenting with various loads, which vary slightly depending on the load amount and dehydration rate, and taking the longest time as the above time (T1), and the difference between the above two temperatures at that time as Iiii + the temperature difference (A).
The deviation is good. However, since the regular hunting state is quite long, it is better to make the time (T1) longer with some margin.

As a result of repeated 77 experiments, it was found that in the case of a heavy load, a steady state was reached after 15 minutes had passed after the start of operation. I decided to make it a minute. When 15 minutes have passed since the start of operation, the temperature at the drum outlet and the temperature at the drum outlet divided by 71σ, which were stored in the RAM after a short update, are calculated and the difference is calculated. , the above-mentioned R as its backside reference value (A)
Memory at another address in AM-4. After that, when the difference between the two measured temperatures becomes (A + 5) degrees (in this example, the above B is 5 degrees),
After finishing the drying operation (defined as
0) and switch to wind-ta (applying J to clothing).If drying operation is still being performed even after 180 minutes have passed since the start of operation, switch to cold-air operation.

If the above temperature detection thermistor (61) < 6 or failure L, the temperature difference between the temperature at the output 10 of the dehumidifier and the temperature at the outlet of the dehumidifier in the case of a small amount of -90 is as shown in Figure (7). Once the constant value is reached, the temperature drops to 0 degrees (A).The reason is that for a while after the start of operation, clothing contains a lot of moisture, so there is a small amount of tangles, so If the hot air is small enough to touch the clothes, it will often be exhausted as it is, so if the temperature at the drum exit is high or a certain amount of moisture is removed from the clothes, the clothes will loosen and spread out, so the hot air will reach the clothes sufficiently. Therefore, the ram exit temperature decreases, and the temperature difference decreases by 0 degrees.

Therefore, the temperature difference A stored at the beginning when the constant 'E Ak state was reached
If the operation is ended at a temperature difference (A to B) without repairing, the drying rate will be over 95%, and drying will continue longer than necessary.
This can cause damage to your clothes, waste electricity, and even damage your clothing.

In the present invention, the temperature difference A is memorized for one day), -+
7゛.

l) When the temperature difference decreases, this decreased temperature <-
A is set as the standard value for the new no, and the king is memorized and rewritten as 1. The operation was then stopped when the temperature difference reached (A'+5) degrees. By performing such treatment, excessive drying can be prevented when the load is small, and a constant drying rate can be obtained regardless of the load.

After switching to drying operation or final rLi cold air operation #jL,'=,
When the drum outlet temperature falls below 40℃, the first relay contact (
79) and stop the morph (41) to end the cold air operation.

In the above embodiment, when the temperature difference between the dehumidifier output temperature and the dehumidifier outlet temperature reaches (A+B) degrees, the drying operation is stopped and the cold air operation is started. After the difference reaches (A+B) degrees, the drying operation may be extended for a time set by a drying rate adjustment timer.

In the following embodiment, a dehumidifier for circulation air duct・＼Name・1
) 11 warm melon drum exit temperature and passing through the dehumidifier in the cooling air path 1. In place of the temperature after passing through the dehumidifier in the cooling air path, install a second sensing element (62) at the position indicated by the dotted chain line in Figure (3). - Determine the temperature after passing through the dehumidifier in the C circulation air path by θ.

That is, measure the temperature difference after the dehumidifier + ij + in the circulation air path [-
Good too. There is a similar change in the temperature difference here and the temperature difference explained earlier from H to C. However, the temperature difference before and after the dehumidifier in the circulating air path smaller than the temperature difference.

Effects of the Invention According to the present invention, the air flow passes through the removal NN of the circulation air path t-6])i
The drying time is controlled by measuring the difference between the temperature after passing through the dehumidifier in the cooling air path and the temperature after passing through the dehumidifier in the circulation air path. It is possible to measure and control the difference between the exhaust gas temperature and the outside air temperature. First, the outside temperature tends to become unstable when the dryer is used indoors, but the temperature after passing through the dehumidifier in the circulation air path or cooling air path is constant. ″
This is because the dry state is constant and stable. Second, in the case of the present invention, even if the circulating air volume changes due to clogging of the noil, or the quasi-tX voltage changes, and the exhaust temperature from the drum changes, in the case of the present invention, the role of the The temperature after passing through the dehumidifier in the circulation air path or cooling air path also changes in response to the change in temperature, and the temperature difference will be the same if the temperature changes.

As described above, the present invention is capable of detecting a constant degree of dryness and terminating drying without being influenced by the external ammonium pick-up load such as the outside air temperature. There is a method that can prevent excessive drying, especially when the load is small.

[Brief explanation of the drawing]

Figure 1 is a front view of the circulating clothes dryer, Figure 2 is a front view of the same with the back plate removed, and Figures 3 and 4 are respectively similar to Figure 1. 5 is a control circuit diagram, and FIGS. 6 and 7 are fluctuation curves of the temperature difference between the drum outlet temperature J hair and the dehumidifying evaporation temperature. Figure 8 shows SO1. j-chart. (6) Drum (drying room), (48) Dehumidifier, 60
〉...Heater, (61)...First heat-sensitive element, (62)
・Second thermal element, (72 buff 3)... heavy pressure comparator,
(74) Rutter circuit, (67)・Microcomputer. Figure 3

Claims (1)

[Claims] (1) In a circulating clothes dryer having a circulating air passage in which exhaust air from a drying chamber is cooled with a dehumidifier to remove moisture, then reheated with a heater and supplied to the drying room, the A first heat-sensitive element that measures the temperature of the air before passing through the dehumidifier, and a temperature of the air after passing through the dehumidifier in the circulation air path, or the outside air is cooled to the dehumidifier. and a second heat-sensitive element that measures the temperature of the air after passing through the dehumidifier in the cooling air path. When a fixed value is reached, the temperature difference is stored as a reference value, and when the difference in the measured temperature becomes lower than this memorized reference value, this lowered temperature difference is replaced as a new standard 1ift. A control method for a circulation type clothes dryer, in which drying operation is ended when the measured temperature difference reaches a predetermined value or more than a reference value determined by 1111, or after a certain period of time has elapsed thereafter.